#二分查找
a = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
def Binary(x, top=0, end=None):
    end = len(a) if end == None else end
    if top < end:
        half = (end-top) // 2+top
        if x < a[half]:
            return  Binary(x, top=top, end=end-1)
        elif x > a[half]:
            return  Binary(x, top=half+1, end=end)
        else:
            return 'Found with subscript:{}'.format(half)
    else:
        return 'not found:{}'.format(x)
x=int(input("Please enter the value you want to find："))
print(Binary(x))
